The present invention relates to providing electrical power to antennas and support electronics mounted on poles.
Wireless systems, such as PCS and cellular systems, typically include a centralized mobile switching center (MSC) responsible for call routing, user location tracking, billing information, and connectivity with other communication systems. The MSC is connected to base station controllers (BSCs), each of which supports one or more base transceiver stations (BTSs). Each BTS supports one or more cells or cell sectors based on the number and configuration of antennas supported by the BTS. A customer communicates with the wireless system through a wireless unit, such as a radio telephone, when the telephone is within the coverage range of a cell. When a call is placed, a circuit-switched connection is established from the telephone, through the BTS and BSC, to the MSC. The MSC determines the destination and, if the destination is to another telephone within the wireless system, establishes a circuit-switched connection to the destination telephone. If the destination is outside of the wireless system, the MSC routes the call to a service provider for the outside destination.
A key component in any wireless communication system is the antenna forming the edge contact between wireless subscribers and the remaining system. Wireless communication antennas are usually elevated to provide increased coverage range. Often, existing structures such as buildings, towers, utility poles, light poles, and the like provide the necessary elevation. Directional antennas are often used to form coverage areas or sectors. Multiple antennas can then be located at one site to provide geographic multiplexing.
When a new antenna location is established, various electrical connections with the antennas must be made. One type of connection carries signals between the antennas and associated transceivers. If transceivers are mounted with the antennas, power cabling and cabling for interconnection with the supporting base station must be provided. This cabling is typically run from the elevated antenna location to pedestals or boxes located on the ground or near the bottom of a pole or tower supporting the antenna. The box provides a convenient location for making power and signal connections. However, the additional work required to mount the box and connect the cabling adds significant cost to the installation of wireless antennas. Such permanent fixtures also make responding to changing communication needs difficult and expensive.
What is needed is to reduce the cabling requirements of wireless antenna installations. A significant component in any wireless antenna installation is providing electrical power to antenna support electronics. The ability to install wireless communication antenna systems without dropping power cabling to boxes or pedestals at the base of the antenna mounting structure would reduce installation costs and permit the antenna systems to be more easily relocated to meet changing communication system requirements.
The present invention provides electrical power to wireless communication antenna systems by tapping into the electrical circuit used to power outdoor elevated lighting systems. These systems include lights mounted on poles, towers or the side of buildings used to illuminate streets, parking lots, playing fields, yards, and a wide variety of outdoor spaces. For brevity, such lighting systems will be called pole mounted street lights. The power connection is made by interrupting the lighting circuit at the electric eye or photocell. Since most electric eyes can be easily removed for replacement, this interruption can typically be accomplished without disturbing the wiring for the light.
In accordance with the present invention, a wireless communication antenna system mounted on a light pole is provided. The light pole supports at least one light driven by a light circuit having an electric eye. The system includes a power adapter between the electric eye and the light circuit. An antenna module is mounted to the pole. At least one electrical cable interconnects the power adapter and the antenna module.
In an embodiment of the present invention, a charge/discharge circuit is connected by electrical cabling between the power adapter and the antenna module. The charge/discharge circuit includes at least one electrical storage device.
In another embodiment of the present invention, the antenna module includes at least one access antenna communicating with subscriber units and at least one backhaul antenna. If more than one backhaul antenna is included, the antenna module further has a packet switch routing information between the backhaul antennas and access antennas. The access antennas may include at least one omnidirectional or directional radio antenna. The antenna module may also include a repeater antenna.
A method of supplying power to a pole mounted antenna module is also provided. Current is drawn from a power adapter inserted between an electric eye and the remaining light circuit controlled by the electric eye.
A method for installing a pole mounted antenna module is also provided. The antenna module is mounted at an elevated location along the pole. A power adapter is inserted between the electric eye and the remainder of the light circuit. The power adapter and the antenna module are interconnected to power the antenna module.
A wireless communication system interconnecting a plurality of wireless subscriber units is also provided. The wireless communication system has a plurality of access points with access antennas for establishing wireless links with subscriber units. At least one access point has an antenna module with at least one access antenna. The antenna module is mounted on a light pole supporting at least one light driven by a light circuit, the light circuit controlled by an electric eye. A power adapter is disposed between the electric eye and the light circuit. At least one electrical cable interconnects the power adapter and the antenna module to provide electrical power to the antenna module.